Question about using the IPv6 benchmarking address space

Hi bmwg,

We would like to use addresses from the IPv6 benchmarking prefix on an independent test network and wonder if there are issues
we have not thought of.

A little background on what we're doing: in OS X El Capitan we introduced a NAT64 mode for the Mac's Internet Sharing feature
to allow iOS developers to test their applications for IPv6 support. Using this, you can share your IPv4 internet connectivity
(e.g. from ethernet) to a newly created Wi-Fi network that only supports IPv6, and the Mac will perform NAT64+DNS64.
Currently the internal addresses of that network are using the Teredo prefix (2001::/64) and we have been advised to use
something that is not treated differently by RFC 6724 (Default Address Selection for IPv6).
We thought that since this is a testing network and that those addresses never leave that link, using the benchmarking prefix
from RFC5180(+ errata) (2001:2/32) would be reasonable. We thought that using 2001:2:a:bb1e/64 as our network prefix
would be appropriate, as "a:bb1e" looks a bit like "apple". Note that this is the prefix advertised by RA to the Wi-Fi network,
it is not the prefix of the NAT64 translation.

Does anyone think there could be any issues with this?

Thanks,
David Schinazi
Apple CoreOS Networking Engineer